backing up wii games

ive got the LG rom that does this and ive done lots on my last pc but i got a new pc last week and get an error when using raw dump is there any way to fix this?
or is there another way of ripping the disc

thanx in advance
here is the error

************** Exception Text **************
System.IO.IOException: An attempt was made to move the file pointer before the beginning of the file.

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

my wii is still on 3.4e rev7 as everything has played so far bar ghostbusters and wii sports resort
so no need to upgrade as of yet but to use the USB Loader to rip the discs to a WBFS formatted HDD i take it i will have to upgrade